package com.lagou.client;

import com.lagou.rpc.JSONSerializer;
import com.lagou.rpc.RpcEncoder;
import com.lagou.rpc.RpcRequest;
import io.netty.bootstrap.Bootstrap;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.codec.string.StringEncoder;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class RpcConsumer {
    // 创建线程池对象
    private static ExecutorService executor = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());

    private static UserClientHandler userClientHandler;

    // 创建代理对象  providerName: UserService#sayHello#are you ok?
    public Object createProxy(final Class<?> serviceClass, final String serviceName, final String methodName) {
        // 借助JDK动态代理对象
        return Proxy.newProxyInstance(Thread.currentThread().getContextClassLoader(), new Class<?>[]{serviceClass}, new InvocationHandler() {
            public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {

                System.out.println("代理"+ method.getName());
                if(!method.getName().equals(methodName)) {
                    // 其他方法不做处理，免得发出不受控制的请求
                    return "";
                }
                // 只代理methodName参数对应的方法
                // 调用初始化netty客户端
                if(userClientHandler == null)
                    initClient();
                // 设置参数
//                userClientHandler.setPara(providerName+args[0]);
                userClientHandler.setPara(new RpcRequest(
                        String.valueOf(System.currentTimeMillis()),
                        serviceName,
                        methodName,
                        method.getParameterTypes(),
                        args
                ));
                // 去服务端请求数据
                return executor.submit(userClientHandler).get();
            }

        });
    }

    // 初始化Netty客户端
    public static void initClient() throws InterruptedException {
        userClientHandler = new UserClientHandler();
        EventLoopGroup group = new NioEventLoopGroup();
        Bootstrap bootstrap = new Bootstrap();
        bootstrap.group(group)
                .channel(NioSocketChannel.class)
                .option(ChannelOption.TCP_NODELAY, true)
                .handler(new ChannelInitializer<SocketChannel>() {
                    protected void initChannel(SocketChannel ch) throws Exception {
                        ChannelPipeline pipeline = ch.pipeline();
//                        pipeline.addLast(new StringEncoder());
                        pipeline.addLast(new RpcEncoder(RpcRequest.class, new JSONSerializer()));
                        pipeline.addLast(new StringDecoder());
                        pipeline.addLast(userClientHandler);
                    }
                });
        bootstrap.connect("127.0.0.1", 8990).sync();
    }
}
